[greenshackle2]

Asyncio is for cooperative multitasking. I/O is the most common use case but it's not the only one. They're using the event loop to schedule their GUI tasks.

Textual is a framework for building desktop apps.

I assume the message queues are in-memory structures used to pass messages between tasks, hence no I/O.

This is really fairly standard stuff.

I understand you may not be familiar with GUI software and/or the Python ecosystem but jumping straight to condescension when you don't understand something is not really a good attitude.